ARLINGTON, Va. — Significant citywide crash reductions followed the introduction of red light cameras in Oxnard, California. This is the key finding of the first U.S. research on the effects of camera enforcement on intersection crashes. The study was conducted by the Insurance Institute for Highway Safety.
Injury crashes at intersections with traffic signals were reduced 29 percent after camera enforcement began in Oxnard in 1997. Front-into-side collisions — the crash type that's most closely associated with red light running — were reduced 32 percent overall, and front-into-side crashes involving injuries were reduced 68 percent.
These results represent more than a single city's success story. They represent solid evidence that red light camera enforcement will reduce crashes at U.S. intersections. Earlier studies showed that cameras reduce the offense of red light running by about 40 percent. But except for a few studies conducted in Australia, there had been little research on how the reduced numbers of violations translated into fewer crashes.
Crashes decline at intersections with and without cameras: Crashes declined throughout Oxnard even though only 11 of the city's 125 intersections with traffic signals are equipped with cameras. Previous U.S. studies of red-light-running violations in Oxnard and elsewhere found similar spillover effects. That is, the violations dropped in about the same proportions at intersections with and without cameras, attesting to the strong deterrent value of red light cameras and their ability to change driver behavior.
The cameras, which are being used to enforce traffic laws in more than 40 U.S. communities, photograph vehicles whose drivers deliberately run red lights. Violators then are ticketed by mail.
"Red light cameras provide the certainty of enforcement, 24 hours a day, 7 days a week," the Institute's senior transportation engineer, Richard Retting, explains. "This has changed the way drivers behave with regard to red light running, and now we can document how this behavior change is reducing crashes and injuries. With the well-publicized use of camera enforcement, communities can make signalized intersections much safer."
In calculating the crash reductions in Oxnard, researchers used changes in crashes in three other California cities without red light cameras — Bakersfield, San Bernardino, and Santa Barbara — as controls.
Camera use is widely favored: Oxnard residents favored red light camera enforcement even before it produced positive effects on crashes. Once the enforcement got under way at city intersections, support increased. Similar support prevails nationwide. Opinions about camera use are favorable in communities with and without enforcement programs, according to a recent Institute survey in 10 cities.
Percent of drivers who favor cameras
|IN CITIES WITH CAMERAS:
||IN CITIES WITHOUT CAMERAS:
||Fort Lauderdale, Florida
|Charlotte, North Carolina
||Raleigh/Durham, North Carolina
|San Francisco, California
Despite this support, officials in many U.S. jurisdictions aren't able to implement camera programs. Only nine states (California, Colorado, Delaware, Hawaii, Maryland, New York, North Carolina, Oregon, and Virginia) and the District of Columbia have laws either granting the use of cameras statewide or allowing them in specific communities. Without explicit authorization, camera use may not be possible.
"The effectiveness of cameras plus the clear public support for using them should persuade state lawmakers to remove the legal hurdles," says Institute president Brian O'Neill.